It is well known, particularly in the field of transporting and using particulate materials, commonly powders, granules, pellets, and the like that it is important to keep product particles as free as possible of contaminants. Particulates are usually transported within a facility where they are to be mixed, packaged or used in a pressurized tubular system that in reality produces a stream of material that behaves somewhat like a fluid. As these materials move through the pipes, considerable friction is generated not only among the particles themselves, but also between the tube walls and the particles in the stream. In turn, this friction results in the development of particle dust, broken particles, fluff, and streamers (ribbon-like elements that can “grow” into quite long and tangled wads that will impede the flow of materials or even totally block the flow). The characteristics of such a transport system are quite well known, as is the importance and value of keeping product particles as free as possible of contaminants.
The term “contaminant” as used herein includes a broad range of foreign material as well as the broken particles, dust, fluff and streamers mentioned in the preceding paragraph. In any case, contaminants are detrimental to the production of a high quality product, and in some situations a health risk to employees of the producer and possibly even a source of danger in that some contaminants can produce a dust cloud which, if exposed to an ignition source, may explode.
Considering product quality, and focusing on moldable plastics as a primary example, foreign material different in composition from the primary material, such as dust, non-uniform material of the primary product, fluff, and streamers, does not necessarily have the same melting temperatures as the primary product and causes flaws when the material is melted and molded. These flaws result in finished products that are not uniform in color, may contain bubbles, and often appear to be blemished or stained, and are, therefore, unsellable. It is important to note that since these same non-uniform materials often do not melt at the same temperature as the primary product, the unmelted contaminants cause friction and premature wear to the molding machines, resulting in downtime, lost production, reduced productivity, increased maintenance and thus increased overall production costs.
Once a specific particulate material has been passed through the dedusting apparatus and a different particulate material is desired to be cleaned through the operation of the dedusting apparatus, the dedusting apparatus needs to be cleaned. Conventional dedusting devices are constructed with horizontal planar surfaces and incomplete welds at the joints and corners due to an inability to get welding equipment properly positioned to form perfect welds. Furthermore, these cracks and corners, along with the horizontal planar surfaces create pockets where particulate material can accumulate and become difficult to remove from the dedusting apparatus. Removal of this accumulated material, whether the accumulated material is dirt or particulate material is important in cleaning the dedusting apparatus for subsequent use as the old particulate material is a contaminate as much as dirt and debris to the new particulate material to be cleaned.
Accordingly, it would be desirable to provide a dedusting apparatus that can be easily cleaned, particularly to be cleaned by spray washing techniques, such that the water is easily drained from the apparatus and such that all the accumulated dirt, debris and remaining particulate material can be removed from the apparatus.